Continuous mining machine with adjustable boring head



M. G. THASSY July 1, 1958 CONTINUOUS MINING MACHINE WITH ADJUSTABLE BORING HEAD 2 Sheets-Sheet 1 Filed July 26, 1957 INVENTOR. BY Michael G Thassy W 7 ATTORNEY July 1, 1958 M. G. THASSY CONTINUOUS MINING MACHINE WITH ADJUSTABLE BORING HEAD 2 SheetsSheet 2 Filed July 26, 1957 INVENTOR. Michael G. Thassy $4M,

ATTORNEY United States Patent Ofilice 2,841,380 Patented July 1, 1958 CONTINUOUS MINING MACHINE WITH ADJUSTABLE BORING HEAD Michael G. Thassy, Chicago, Ill., assignor to Goodman Manufacturing Company, Chicago, 111., a corporation of Illinois Application July 26, 1957, Serial No. 674,448

3 Claims. c1. 262-26) This invention relates to improvements in boring heads for mining machines in which at least one boring head is rotatable on a horizontal axis in advance of the machine. More particularly, the invention relates to the type of telescopic adjustment for the outer end of a boring head arm, such as shown in my application, Serial No. 621,678, filed November 13, 1956, now Patent No. 2,798,708.

The principal object of the present invention is to provide a simple form and arrangement of means for adjusting the telescopic end portion of a boring head arm relative to its hub.

The invention may best be understood by reference to the accompanying drawings, in which- Figure l is a longitudinal section of a boring head and arm constructed in accordance with the invention;

Figure 2 is a detail section of the hub portion of the head drawn to a larger scale than Figure l; and

Figure 3 is a detail section showing the rear end of the drive shaft and associated parts drawn to a larger scale than Figure l.

Referring now to details of the embodiment of the invention shown in the drawings, indicates the drive shaft of a boring head mounted for rotation in bearings 11 and 12, and driven by gear 13. The bearings 11 and 12 are mounted in the gear case 14 which is a portion of an auxiliary frame forming part of a mining machine. Trimming chain guide 116 is telescopically mounted on the auxiliary frame and forms part of the usual equipment found on mining machines of the type to which the present invention is directed.

The boring head 10 has a hollow hub 20 at its front end on which is fixed a center drill base 19, which has a wedging surface 21, bit holders 22 and cutter bits 23 at its front end. A radial arm 24 extends'from the hub 20 and has a telescopically extensible arm 26 mounted therein. The radial arms 24 may have a forwardly projecting cutter support 27 fixed thereon with a wedging washer 66 is held against an inner shoulder 64 of anand its associated parts are shown in greater detail.

surface 28 and bit holders 22 and bits 23. The telescopic arm 26 has a forwardly extending cutter support 29 mounted on its outer extremity with bit holders 22 and bits 23 mounted thereon.

The telescopic arm 26 has an axial bore 49 sealed at its outer end by plug 51. The inner end of the bore terminates in a shoulder 52 and a threaded bore 53. The threaded bore 53 terminates in a counter bore 56 having a shoulder 54. An extension screw having threads 58 engages the threaded bore 53. The end of said screw is secured in the bore 49 by a nut 72 and a concave washer 73, commonly called a coned spring. A second coned spring 57 in the opposite counter bore 56 is mounted to slip freely over the threads 58 of the screw and may from time to time act as a resilient spacer between shoulder 54 of the telescopic arm and a shoulder 59 at the opposite end of the screw. Opposite shoulder 62 on screw 58 bears against the pad 61 in the hub of boring head 10. An annular portion 63 of the screw is rotatably fitted in bore 41 of head 10. A flat thrust end portion 67 of the screw as by key 69 and nut 71. The parts of the telescopic boring arm are similar to those disclosed in my prior application, Serial No. 621,678, filed November 13, 1956.

Referring now to details of the control means forming the subject matter of the present invention, the gear 68 Gear 68 is intermeshed with gears 76 and 77 which are spaced apart by a tubular spacer 78. Gear 77 is rotatably journaled in bore 79 ofhead 10 and gear 76'is rotatably journaled in bore 81, both of which bores are concentric with the axis of head 10. The gear 77 abuts a shoulder 82 in head 10 and gear 76 abuts a shoulder 83'on center drill 19 so as to locate the axial positions of the gears 76 and 77. The outer faces of both gears 76 and 77 are recessed to form clutch housings, and internal splines 84 and 86 are formed in the gears 77 and 76 which are engaged by alternate discs 87 of a stack of friction disc members. The other friction discs 88 engage splines 89 of flanged sleeves 91 and 92, which are fixed to a shaft 93 as by keys 94.

Annular pistons 96 and 98 are slidable on sleeves 91 and 92 between the end flanges 911 and 921 of said sleeves and the friction discs in the housings of gears 76 and 77 respectively. The outer surfaces of the annular pistons 96 and 98 and the outer surfaces of sleeves 91 and 92 are grooved to receive 0 rings 97 and 99 respectively, to provide fluid tight seals for the pistons.

Flanged sleeves 91 and 92 have fluid ports 193, 164 which register with passages 106 and 107 in shaft 93 to provide a passage for pressure fluid to the pistons 96 and 98. The front end of shaft 93 is axially secured but rotatably mounted in the center drill base by means of snap ring 108, bearing 109, and lock nut 111. The rear end of shaft 93 terminates adjacent flanged sleeve 92, and has a tubular member 112 secured to it as by welding. The end of the shaft is tapped to secure conduits 113 and 114 which communicate with passages 107 and 106.

Referring now to Figure 3, the tubular member 112 is fixed as by key 116 to a supporting member 117 which is itself fixed to the gear case 14 as by key 118. Thus the shaft 93 and flanged sleeves 91 and 92 are kept from rotating relative to the gear case 14, while the head 10 is free to rotate.

The ends of conduit 113 and 114 are grooved to accept 0 rings 119 and 121 which when slipped into bores in the support 117 form a fluid tight seal. Passages 122 and 123 in support 117 communicate with the conduits 113 and 114, and connect on their other end to conventional pressure control means, not shown.

In operation, the drive shaft 161, hub 20 and arm 24 are rotated as usual by the gear 13, but the parts on which the gears 76 and 77 are rotatably supported within the hub 20 are fixed against rotation by the supporting member 117 which is keyed to the gear case 14 at the rear end of the drive shaft 10, and is connected through a tube 112 passing forwardly through said drive shaft to the shaft 93 and flanged sleeves 91 and 92 within the hollow hub 20.

In normal operation, the two gears '76 and 77 both remain in meshed relation with the gear 68 fixed on the screw 58, but no driving effect is imparted to said screw during rotation of the boring head while the clutch plates associated with the two gears 76 and 77 are disengaged.

When it is desired to extend or retract the telescopic arm 26, fluid pressure is admitted to one or the other conduits 113 or 11 so as to engage the clutch plates associated with one or the other gears 76 or 77.

For instance, the engagement of the clutch plates associated with gear 76 will arrest the rotation of the latter gear, whereupon continued rotation of the' head as a whole will cause the screw ;58 to be rotated'in a direction to extend or retract the telescopic arm 26 depending upon whether said screw has a right or left hand thread, When fluid pressure is released from the positionassociated with gear 76, the latter gear will again be free for rotation relative to the shaft 93, whereupon any further driving efiect on the screw 58 will be discontinued. V V p Conversely, when it is desiredto adjust the telescopic arm 26 in the opposite direction, fiuid' pressure is ad- 'mitt ed through the pipe 114 to impose pressure through annular piston 98 upon the clutch plates associated with the gear 77 to arrest rotation of the latter and cause the screwed to rotate in the opposite direction. 7

7 When the telescopic arm 2 6 is eitherex ten ded or retracted to its limit of movement in either direction, as determinedby engagement with either the coned spring 57 or 73, further rotation of the screw 58 will be discontinued due to slippage afforded between the clutch gear 76: or 77, thus protecting the inner arm portion extending radially from said'hub and separated'from said hollow hub by a transverse partition, a cutter-carrying end portion telescopically mounted inthe outer end of said inner radial arm portion, an extension screw extending radially of said inner arm portion, with its outer end in threaded engagement with said telescopic outer end portion and its inner end extending through and having bearing engagement in' said transverse partition, a gear fixed on the inner end of said extension screw within said hollow hub, an anchoring member having its inner end fixed to said frame and extending forwardly through said hollow drive shaft and into said hollow hub, a pair of opposed gears adapted normally for free rotation in said hollowhub and each meshed with opposite sides of the gear on said exten sion screw, and clutch means associated with each of said gears for selectively connecting them to the anchoring member in said hub to restrain free rotation thereof, thereby causing rotation of said extension screw in one direction or the other, due to rotation of said hub.

2. The structure of claim, 1, wherein the clutch-means- 7 associated with each of the opposed gears in the hub is actuated by fluid pressure means including separate prssure suppl'y' ductsextending along the anchoring member from beyond the rear end of the drive shaft.

7 3. The structure of claim 2, wherein the fluid pressure means for selectively actuating the clutch means associated with the two opposed gears each includes a plurality of clutch plates alternately connected with its respective 2,798,708 Thassy July 9,1951 

